Systems and methods for acknowledging communications from a plurality of devices

ABSTRACT

Systems, methods, and devices for acknowledging communications from a plurality of devices for acknowledging communications from a plurality of devices are described herein. In some aspects, a group ACK includes a bitmap indicating whether a communication has been received from each of a plurality of apparatuses within a previous period. The previous period may comprise a time period since a previous ACK. In some aspects, group ACKs are transmitted pursuant to a schedule. For example, group ACKs may be transmitted a scheduled time after transmitting a beacon. In some aspects, a bitmap indicating whether a communication has been received from each of a plurality of apparatuses within a previous period may be transmitted in a beacon.

CROSS REFERENCE TO RELATED APPLICATION(S)

This application claims the benefit of U.S. Provisional Application No.61/495,256, filed Jun. 9, 2011, the entire content of which isincorporated herein by reference.

BACKGROUND

1. Field

The present application relates generally to wireless communications,and more specifically to systems, methods, and devices for acknowledgingcommunications from a plurality of devices.

2. Background

In many telecommunication systems, communications networks are used toexchange messages among several interacting spatially-separated devices.Networks may be classified according to geographic scope, which couldbe, for example, a metropolitan area, a local area, or a personal area.Such networks would be designated respectively as a wide area network(WAN), metropolitan area network (MAN), local area network (LAN),wireless local area network (WLAN), or personal area network (PAN).Networks also differ according to the switching/routing technique usedto interconnect the various network nodes and devices (e.g. circuitswitching vs. packet switching), the type of physical media employed fortransmission (e.g. wired vs. wireless), and the set of communicationprotocols used (e.g. Internet protocol suite, SONET (Synchronous OpticalNetworking), Ethernet, etc.).

Wireless networks are often preferred when the network elements aremobile and thus have dynamic connectivity needs, or if the networkarchitecture is formed in an ad hoc, rather than fixed, topology.Wireless networks employ intangible physical media in an unguidedpropagation mode using electromagnetic waves in the radio, microwave,infra-red, optical, etc. frequency bands. Wireless networksadvantageously facilitate user mobility and rapid field deployment whencompared to fixed wired networks.

The devices in a wireless network may transmit/receive informationbetween each other. As part of this communication process, a firstdevice that receives information from a second device may transmit anacknowledgment (ACK) to the second device acknowledging that the firstdevice received the information. The act of transmitting anacknowledgment adds additional overhead to communications in thewireless network.

This additional overhead may be especially problematic in some wirelessnetworks. For example, in some areas, such as in Europe, some spectrums(e.g., wireless channels, frequency bands, etc.) have a transmit dutycycle restriction of 100 seconds per hour. In these areas, a giventransmitter is only allowed to transmit in those spectrums for 100seconds or less in a given hour. In some cases, such as for devicescollecting measurements from sensors, the overhead of sending ACKs alonemay exceed this duty cycle restriction. Thus, improved systems, methods,and devices for communicating ACKs are desired.

SUMMARY

The systems, methods, and devices of the invention each have severalaspects, no single one of which is solely responsible for its desirableattributes. Without limiting the scope of this invention as expressed bythe claims which follow, some features will now be discussed briefly.After considering this discussion, and particularly after reading thesection entitled “Detailed Description” one will understand how thefeatures of this invention provide advantages that include transmittingand/or receiving an ACK that includes information signifying whetherinformation was received from each of a plurality of devices, therebyreducing the overhead in transmitting ACKs.

One aspect of the disclosure provides a method of communicating in awireless network. The method includes determining whether acommunication has been received from each of a plurality of apparatuseswithin a previous period, generating a plurality of indicators, andwirelessly broadcasting a communication comprising the plurality ofindicators. In some aspects, each indicator signifies a result of thedetermination for a respective one of the plurality of apparatuses.

Another aspect of the disclosure provides an apparatus for communicatingin a wireless network. The apparatus includes a processor configured todetermine whether a communication has been received from each of aplurality of apparatuses within a previous period and further configuredto generate a plurality of indicators, and a transmitter configured towirelessly broadcast a communication comprising the plurality ofindicators. In some aspects, each indicator signifies a result of thedetermination for a respective one of the plurality of apparatuses.

Another aspect of the disclosure provides an apparatus for communicatingin a wireless network. The apparatus includes means for determiningwhether a communication has been received from each of a plurality ofapparatuses within a previous period, means for generating a pluralityof indicators, and means for wirelessly broadcasting a communicationcomprising the plurality of indicators. In some aspects, each indicatorsignifies a result of the determination for a respective one of theplurality of apparatuses.

Another aspect of the disclosure provides a computer readable medium.The computer readable medium includes instructions that when executedcause an apparatus to determine whether a communication has beenreceived from each of a plurality of apparatuses within a previousperiod, generate a plurality of indicators, and wirelessly broadcast acommunication comprising the plurality of indicators. In some aspects,each indicator signifies a result of the determination for a respectiveone of the plurality of apparatuses.

Another aspect of the disclosure provides a method of communicating in awireless network. The method includes wirelessly transmitting a firstcommunication to a first apparatus and wirelessly receiving a secondcommunication from the first apparatus. In some aspects, the secondcommunication includes a plurality of indicators signifying whether thefirst apparatus received a communication from each of a plurality ofapparatuses. The method further includes determining whether the firstcommunication was received by the first apparatus based on at least oneindicator of the plurality of indicators.

Another aspect of the disclosure provides an apparatus for communicatingin a wireless network. The apparatus includes a transmitter configuredto wirelessly transmit a first communication to a first apparatus, and areceiver configured to wirelessly receive a second communication fromthe first apparatus. In some aspects, the second communication includesa plurality of indicators signifying whether the first apparatusreceived a communication from each of a plurality of apparatuses. Theapparatus further includes a processor configured to determine whetherthe first communication was received by the first apparatus based on atleast one indicator of the plurality of indicators.

Another aspect of the disclosure provides an apparatus for communicatingin a wireless network. The apparatus includes means for wirelesslytransmitting a first communication to a first apparatus, and means forwirelessly receiving a second communication from the first apparatus. Insome aspects, the second communication includes a plurality ofindicators signifying whether the first apparatus received acommunication from each of a plurality of apparatuses. The apparatusfurther includes means for determining whether the first communicationwas received by the first apparatus based on at least one indicator ofthe plurality of indicators.

Another aspect of the disclosure provides a computer readable medium.The computer readable medium includes instructions that when executedcause an apparatus to wirelessly transmit a first communication to afirst apparatus, and wirelessly receive a second communication from thefirst apparatus. In some aspects, the second communication includes aplurality of indicators signifying whether the first apparatus receiveda communication from each of a plurality of apparatuses. When executed,the instructions further cause an apparatus to determine whether thefirst communication was received by the first apparatus based on atleast one indicator of the plurality of indicators.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communication system inwhich aspects of the present disclosure may be employed.

FIG. 2 illustrates various components that may be utilized in a wirelessdevice that may be employed within the wireless communication system ofFIG. 1.

FIG. 3 illustrates an example of an acknowledgment (ACK) of a type usedin certain systems for communication.

FIG. 4 illustrates an example of a plurality of indicators that may beused in a group ACK within the wireless communication system of FIG. 1.

FIG. 5 illustrates an aspect of a method for transmitting a group ACK.

FIG. 6 is a functional block diagram of another exemplary wirelessdevice that may be employed within the wireless communication system ofFIG. 1.

FIG. 7A illustrates an aspect of a method for receiving a group ACK.

FIG. 7B illustrates another aspect of a method for receiving a groupACK.

FIG. 8 is a functional block diagram of another exemplary wirelessdevice that may be employed within the wireless communication system ofFIG. 1.

DETAILED DESCRIPTION

Various aspects of the novel systems, apparatuses, and methods aredescribed more fully hereinafter with reference to the accompanyingdrawings. The teachings of this disclosure may, however, be embodied inmany different forms and should not be construed as limited to anyspecific structure or function presented throughout this disclosure.Rather, these aspects are provided so that this disclosure will bethorough and complete, and will fully convey the scope of the disclosureto those skilled in the art. Based on the teachings herein one skilledin the art should appreciate that the scope of the disclosure isintended to cover any aspect of the novel systems, apparatuses, andmethods disclosed herein, whether implemented independently of orcombined with any other aspect of the invention. For example, anapparatus may be implemented or a method may be practiced using anynumber of the aspects set forth herein. In addition, the scope of theinvention is intended to cover such an apparatus or method which ispracticed using other structure, functionality, or structure andfunctionality in addition to or other than the various aspects of theinvention set forth herein. It should be understood that any aspectdisclosed herein may be embodied by one or more elements of a claim.

Although particular aspects are described herein, many variations andpermutations of these aspects fall within the scope of the disclosure.Although some benefits and advantages of the preferred aspects arementioned, the scope of the disclosure is not intended to be limited toparticular benefits, uses, or objectives. Rather, aspects of thedisclosure are intended to be broadly applicable to different wirelesstechnologies, system configurations, networks, and transmissionprotocols, some of which are illustrated by way of example in thefigures and in the following description of the preferred aspects. Thedetailed description and drawings are merely illustrative of thedisclosure rather than limiting, the scope of the disclosure beingdefined by the appended claims and equivalents thereof.

Popular wireless network technologies may include various types ofwireless local area networks (WLANs). A WLAN may be used to interconnectnearby devices together, employing widely used networking protocols. Thevarious aspects described herein may apply to any communicationstandard, such as WiFi or, more generally, any member of the IEEE 802.11family of wireless protocols. For example, the various aspects describedherein may be used as part of a WiFi advanced protocol, such as the IEEE802.11 WiFi Advanced-N protocol, or the IEEE 802.11ah protocol, whichuses sub-1 GHz bands.

In some aspects, wireless signals in a sub-gigahertz band may betransmitted according to the 802.11ah protocol using orthogonalfrequency-division multiplexing (OFDM), direct-sequence spread spectrum(DSSS) communications, a combination of OFDM and DSSS communications, orother schemes. Implementations of the 802.11ah protocol may be used forsensors, metering, and smart grid networks. Advantageously, aspects ofcertain devices implementing the 802.11ah protocol may consume lesspower than devices implementing other wireless protocols, and/or may beused to transmit wireless signals across a relatively long range, forexample about one kilometer or longer.

In some implementations, a WLAN includes various devices which are thecomponents that access the wireless network. For example, there may betwo types of devices: access points (“APs”) and clients (also referredto as stations, or “STAB”). In general, an AP serves as a hub or basestation for the WLAN and an STA serves as a user of the WLAN. Forexample, an STA may be a laptop computer, a personal digital assistant(PDA), a mobile phone, etc. In an example, an STA connects to an AP viaa WiFi (e.g., IEEE 802.11 protocol such as 802.11ah or WiFi Advanced-N)compliant wireless link to obtain general connectivity to the Internetor to other wide area networks. In some implementations an STA may alsobe used as an AP.

An access point (“AP”) may also comprise, be implemented as, or known asa NodeB, Radio Network Controller (“RNC”), eNodeB, Base StationController (“BSC”), Base Transceiver Station (“BTS”), Base Station(“BS”), Transceiver Function (“TF”), Radio Router, Radio Transceiver, orsome other terminology.

A station “STA” may also comprise, be implemented as, or known as anaccess terminal (“AT”), a subscriber station, a subscriber unit, amobile station, a remote station, a remote terminal, a user terminal, auser agent, a user device, user equipment, or some other terminology. Insome implementations an access terminal may comprise a cellulartelephone, a cordless telephone, a Session Initiation Protocol (“SIP”)phone, a wireless local loop (“WLL”) station, a personal digitalassistant (“PDA”), a handheld device having wireless connectioncapability, or some other suitable processing device connected to awireless modem. Accordingly, one or more aspects taught herein may beincorporated into a phone (e.g., a cellular phone or smartphone), acomputer (e.g., a laptop), a portable communication device, a headset, aportable computing device (e.g., a personal data assistant), anentertainment device (e.g., a music or video device, or a satelliteradio), a gaming device or system, a wireless sensor device, a globalpositioning system device, or any other suitable device that isconfigured to communicate via a wireless medium.

As discussed above, certain of the devices described herein mayimplement the 802.11ah standard or a WiFi Advanced-N standard, forexample. Such devices, whether used as an STA or AP or other device, maybe used for smart metering or in a smart grid network. Such devices mayprovide sensor applications or be used in home automation. The devicesmay instead or in addition be used in a healthcare context, for examplefor personal healthcare. They may also be used for surveillance, toenable extended-range Internet connectivity (e.g. for use withhotspots), or to implement machine-to-machine communications.

FIG. 1 illustrates an example of a wireless communication system 100 inwhich aspects of the present disclosure may be employed. The wirelesscommunication system 100 may operate pursuant to a wireless standard,for example the 802.11ah standard or a WiFi Advanced-N standard. Thewireless communication system 100 may include an AP 104, whichcommunicates with STAs 106.

A variety of processes and methods may be used for transmissions in thewireless communication system 100 between the AP 104 and the STAs 106.For example, signals may be sent and received between the AP 104 and theSTAs 106 in accordance with OFDM/OFDMA techniques. If this is the case,the wireless communication system 100 may be referred to as anOFDM/OFDMA system. Alternatively, signals may be sent and receivedbetween the AP 104 and the STAs 106 in accordance with CDMA techniques.If this is the case, the wireless communication system 100 may bereferred to as a CDMA system.

A communication link that facilitates transmission from the AP 104 toone or more of the STAs 106 may be referred to as a downlink (DL) 108,and a communication link that facilitates transmission from one or moreof the STAs 106 to the AP 104 may be referred to as an uplink (UL) 110.Alternatively, a downlink 108 may be referred to as a forward link or aforward channel, and an uplink 110 may be referred to as a reverse linkor a reverse channel.

The AP 104 may act as a base station and provide wireless communicationcoverage in a basic service area (BSA) 102. The AP 104 along with theSTAs 106 associated with the AP 104 and that use the AP 104 forcommunication may be referred to as a basic service set (BSS). It shouldbe noted that the wireless communication system 100 may not have acentral AP 104, but rather may function as a peer-to-peer networkbetween the STAs 106. Accordingly, the functions of the AP 104 describedherein may alternatively be performed by one or more of the STAs 106.

FIG. 2 illustrates various components that may be utilized in a wirelessdevice 202 that may be employed within the wireless communication system100. The wireless device 202 is an example of a device that may beconfigured to implement the various methods described herein. Forexample, the wireless device 202 may comprise the AP 104 or one of theSTAs 106.

The wireless device 202 may include a processor 204 which controlsoperation of the wireless device 202. The processor 204 may also bereferred to as a central processing unit (CPU). Memory 206, which mayinclude both read-only memory (ROM) and random access memory (RAM),provides instructions and data to the processor 204. A portion of thememory 206 may also include non-volatile random access memory (NVRAM).The processor 204 typically performs logical and arithmetic operationsbased on program instructions stored within the memory 206. Theinstructions in the memory 206 may be executable to implement themethods described herein.

In some aspects, the processor 204 is configured to determine whetherthe wireless device 202 has received a communication from each of aplurality of apparatuses, for example using a receiver 212. In someaspects, the processor is further configured to generate a plurality ofindicators that each signify a result of the determination for arespective one of the plurality of apparatuses. The processor 204 mayinclude the plurality of indicators in a bitmap and/or an informationelement. The plurality of indicators may be included in a group ACK,described in additional detail below, that is broadcast to the pluralityof apparatuses, for example using a transmitter 210.

In some aspects, the processor 204 is configured to process at least aportion of a group ACK received at the wireless device 202 using thereceiver 212. If the wireless device 202 is waiting for an ACK for apreviously transmitted communication, the processor 204 may determinewhether the communication was properly received by a device transmittingthe group ACK based on at least one of a plurality of indicators in thegroup ACK. Each of the plurality of indicators may signify whether thedevice transmitting the group ACK received a communication from arespective apparatus of a plurality of apparatuses. If the wirelessdevice 202 is not waiting for an ACK for a previously transmittedcommunication, the wireless device 204 may halt reception of the groupACK or otherwise ignore the group ACK.

The processor 204 may comprise or be a component of a processing systemimplemented with one or more processors. The one or more processors maybe implemented with any combination of general-purpose microprocessors,microcontrollers, digital signal processors (DSPs), field programmablegate array (FPGAs), programmable logic devices (PLDs), controllers,state machines, gated logic, discrete hardware components, dedicatedhardware finite state machines, or any other suitable entities that canperform calculations or other manipulations of information.

The processing system may also include machine-readable media forstoring software. Software shall be construed broadly to mean any typeof instructions, whether referred to as software, firmware, middleware,microcode, hardware description language, or otherwise. Instructions mayinclude code (e.g., in source code format, binary code format,executable code format, or any other suitable format of code). Theinstructions, when executed by the one or more processors, cause theprocessing system to perform the various functions described herein.

The wireless device 202 may also include a housing 208 that includes thetransmitter 210 and/or the receiver 212 to allow transmission andreception of data between the wireless device 202 and a remote location.The transmitter 210 and receiver 212 may be combined into a transceiver214. An antenna 216 may be attached to the housing 208 and electricallycoupled to the transceiver 214. The wireless device 202 may also include(not shown) multiple transmitters, multiple receivers, multipletransceivers, and/or multiple antennas.

As alluded to above, the transmitter 210 may be configured to wirelesslytransmit data packets and/or ACKs, for example group ACKs. Further, thereceiver 212 may be configured to wirelessly receive data packets and/orACKs, for example group ACKs.

The wireless device 202 may also include a signal detector 218 that maybe used in an effort to detect and quantify the level of signalsreceived by the transceiver 214. The signal detector 218 may detect suchsignals as total energy, energy per subcarrier per symbol, powerspectral density, and other signals. The wireless device 202 may alsoinclude a digital signal processor (DSP) 220 for use in processingsignals. The DSP 220 may be configured to generate a packet fortransmission. In some aspects, the packet may comprise a physical layerconvergence procedure (PLCP) protocol data unit (PPDU).

The wireless device 202 may further comprise a user interface 222 insome aspects. The user interface 222 may comprise a keypad, amicrophone, a speaker, and/or a display. The user interface 222 mayinclude any element or component that conveys information to a user ofthe wireless device 202 and/or receives input from the user.

The various components of the wireless device 202 may be coupledtogether by a bus system 226. The bus system 226 may include a data bus,for example, as well as a power bus, a control signal bus, and a statussignal bus in addition to the data bus. Those of skill in the art willappreciate the components of the wireless device 202 may be coupledtogether or accept or provide inputs to each other using some othermechanism.

Although a number of separate components are illustrated in FIG. 2,those of skill in the art will recognize that one or more of thecomponents may be combined or commonly implemented. For example, theprocessor 204 may be used to implement not only the functionalitydescribed above with respect to the processor 204, but also to implementthe functionality described above with respect to the signal detector218 and/or the DSP 220. Further, each of the components illustrated inFIG. 2 may be implemented using a plurality of separate elements.

As discussed above, the wireless device 202 may comprise an AP 104 or anSTA 106, and may be used to transmit and/or receive communicationsincluding ACKs and other packets. For ease of reference, when thewireless device 202 is configured as a transmitting node, it ishereinafter referred to as a wireless device 202 t. Similarly, when thewireless device 202 is configured as a receiving node, it is hereinafterreferred to as a wireless device 202 r. A device in the wirelesscommunication system 100 may implement only functionality of atransmitting node, only functionality of a receiving node, orfunctionality of both a transmitting node and a receive node.

FIG. 3 illustrates an example of an ACK 300, of a type used in certainsystems for communication. For example, the ACK 300 includes 4 fields: aframe control (fc) field 305, a duration/identification (dur) field 310,a receiver address (a1) field 315, and a frame control sequence (fcs)field 320. In such systems, the ACK 300 may be transmitted by a wirelessdevice 202 r to a wireless device 202 t after the wireless device 202 rreceives a data packet transmitted from the wireless device 202 t. TheACK 300 indicates to the wireless device 202 t that it received the datapacket. The wireless device 202 t can therefore verify transmission ofthe data packet to the wireless device 202 r. The wireless device 202 tcan determine that the ACK 300 is from the wireless device 202 r basedon the a1 field 315, which indicates the address of the wireless device202 r.

In some situations, transmitting separate ACKs to each device from whicha communication has been received may be prohibitive because suchtransmission creates too much overhead. For example, in some areas, suchas in Europe, some spectrums (e.g., wireless channels, frequency bands,etc.) have a transmit duty cycle restriction of 100 seconds per hour. Inthese areas, a given transmitter is only allowed to transmit in thosespectrums for 100 seconds or less in a given hour. In some cases, suchas for devices collecting measurements from sensors, the overhead ofsending ACKs alone may exceed this duty cycle restriction. Therefore,transmission of the entire ACK 300 from the wireless device 202 r toeach wireless device 202 t may not be feasible. For example, when the AP104 is receiving communications from a plurality of the STAs 106, it maynot be feasible for the AP 104 to send separate ACKs to each of the STAs106.

Accordingly, systems, methods, and devices for using a single ACK whichalerts a plurality of wireless devices 202 t whether their communicationwas received are described herein. Such a “group ACK,” as it may bereferred to, may reduce the overhead of sending ACKs in thecommunication system 100 because separate PHY headers and padding arenot needed for each individual ACK. Instead, data for acknowledgingcommunications from a plurality of apparatuses may be included with asingle PHY header. Thus, less data may be transmitted overall in thecommunication system 100. Less transmission of data may increase thespeed with which data is transmitted, may reduce the use of bandwidth bya transmitter, and may reduce the power utilized for transmission asfewer resources are used to transmit the reduced amount of data.

FIG. 4 illustrates an example of a plurality 400 of indicators that maybe used in a group ACK within the wireless communication system 100.Each of the plurality of indicators 402-412 indicates to a respectiveapparatus whether the device transmitting the plurality 400 has receiveda communication or other information from the apparatus. In someaspects, the plurality 400 may be included in an information element(IE) within a packet.

In some aspects, the plurality 400 is transmitted according to aschedule. For example, the plurality 400 may be periodically broadcastby the AP 104 to the STAs 106 once every 100 milliseconds. In someaspects, the plurality 400 is included in a beacon that is periodicallytransmitted by the AP 104 to the STAs 106. In other aspects, theplurality 400 is included in a group ACK that is separate from thebeacon. In these aspects, the group ACK may be transmitted a given timeperiod or a given number of communications after the beacon. Thus, theperiodicity with which the plurality 400 is transmitted and/or receivedmay be determined by the regularity of the beacon. In other aspects, theschedule for transmitting the group ACK is defined independent of thebeacon.

The schedule of transmitting the plurality 400 may be stored in thememory 206, for example at the time of manufacturing the wireless device202. In some aspects, the schedule is communicated to one or more of theSTAs 106 by the AP 104, for example during the process of associatingthe STA 106 with the AP 104.

In some aspects, one or more of the indicators 402-412 includesinformation identifying a previous communication received from arespective apparatus. For example, a sequence number of the previouscommunication may be included in the indicator. In this way, anapparatus receiving the indicator may identify which of a plurality ofprevious communications is being acknowledged in the plurality 400. If asequence number is not included in the indicator, the apparatus maydetermine that a previously transmitted communication was not received.

In other aspects, an apparatus receiving the plurality 400 may be ableto determine which of the plurality of previous communications is beingacknowledged based on a time at which the plurality 400 is received bythe apparatus. For example, each of the plurality of indicators 402-412may indicate to a respective apparatus whether the device transmittingthe plurality 400 has received a communication or other information fromthe apparatus since a previous ACK was transmitted to the apparatus.

In some aspects, received communications are only acknowledged in theform of group ACKs, which may be included in the beacon or separatelytransmitted. In these aspects, each of the indicators 402-412 willtherefore signify whether a communication or other information has beenreceived from a respective apparatus since a previous group ACK.

In some aspects, reception of certain communications may be acknowledgedby an individual ACK, for example an ACK that is addressed solely to theapparatus which transmitted the communication. For example, low-latencyand/or high priority communications may be acknowledged by the AP 104 asthe AP 104 receives them, as opposed to waiting until the next group ACKfor acknowledgement. Thus, one or more individual ACKs may betransmitted between group ACKs in some aspects. In these aspects, thetime period to which each of the indicators 402-412 pertains may differ.For example, the indicator 402 may indicate to a first apparatus whethera communication has been received from the first apparatus since aprevious group ACK, while the indicator 404 may indicate to a secondapparatus whether a communication has been received from the secondapparatus since a previous individual ACK, where the individual ACK wastransmitted after the previous group ACK. The time period covered by thesecond indicator 404 would therefore be shorter than the time periodcovered by the first indicator 402.

In some aspects, each apparatus communicating with the device thattransmits the plurality 400 is assigned an association identifier (AID).For example, each of the STAs 106 communicating with the AP 104 may beassigned a unique AID. In these aspects, an apparatus receiving theplurality 400 may determine which of the indicators 402-412 to analyzebased the apparatus's AID.

For example, the STAs 106 may each be assigned an AID that has a valueranging from 1 to N. One of the STAs 106 may determine whether the AP104 properly received a communication from the one STA by indexing intothe plurality 400 with the one STA's AID, and evaluating the indicatorat that index. As an example, when an apparatus which as been assignedAID of 3 receives the plurality 400, the apparatus may evaluate theindicator 406 (the third indicator) to determine if a communicationpreviously transmitted by the apparatus was received.

As another example, the STAs 106 may each be assigned an AID that has avalue ranging from 1+X through N+X. To determine whether the AP 104properly received a communication from one of the STAs 106, the one STAmay evaluate the indicator positioned at index AID-X.

In some aspects, the AIDs of the apparatuses to which the plurality 400is directed are not sequential. In these aspects, the AID may notdirectly correspond to an indicator index, but an order of theindicators 402-412 may still be determined based on the relative valuesof the AIDs. Those having ordinary skill in the art will recognize othermethods that may be used to sequence, position, or arrange theindicators 402-412 based on an AID of the respective apparatus to whichthe each of the indicators 402-412 pertains.

In some aspects, the plurality 400 is implemented using a bitmap. Inthese aspects, each of the indicators 402-412 is represented by a bit.For example, a value of “0” in one of the indicators 402-412 mayindicate that a communication has not been received from an apparatus,while a value of “1” in the indicator may signify that a communicationhas been received from the apparatus. In some aspects, these values arereversed.

When the plurality 400 is implemented using a bitmap and the indicators402-412 are arranged according to the AIDs of the apparatuses associatedwith the device transmitting the plurality 400, the plurality 400 mayresemble a traffic indication map (TIM). Instead of each bit in thebitmap indicating whether a frame is buffered for a respectiveapparatus, as in the TIM, each bit of the bitmap implementing theplurality 400 indicates whether a frame or packet has been received froma respective apparatus since a previous ACK was transmitted to therespective apparatus. In some such aspects, the array of indicators402-412 may be referred to as an ACK TIM due to the similarity with theTIM. In some aspects, a subset of the indicators 402-412 may be includedin the plurality 400, similar to the way in which a partial virtualbitmap may be included in the TIM.

In the aspect illustrated in FIG. 4, five indicators 402-412 are shown.The plurality 400 may, however, include a greater or fewer number ofindicators. For example, the plurality 400 may include two indicators insome aspects. In other aspects, the plurality 400 includes three or fourindicators. In some aspects, the plurality 400 includes greater thanfive indicators, such as 2008 indicators or more.

As discussed above, the plurality 400 may be transmitted in a group ACKby a wireless device 202 r after the device receives an incoming datapacket from one or more wireless devices 202 t. Before sending the groupACK and after receiving the incoming data packet(s), the wireless device202 r may further decode the data packet(s) and check to see if a framecontrol sequence (for example a cyclic redundancy check) of the datapacket(s) passes, thereby indicating that there are no errors in thereception of the data packet(s). In some aspects, an indicatorsignifying that the data packet(s) was correctly received is only set ifthe frame control sequence passes.

FIG. 5 illustrates an aspect of a method 500 for transmitting a groupACK. The method 500 may be used to transmit the plurality 400illustrated in FIG. 4, or another suitable plurality of indicators basedon the teachings herein. The plurality 400 may be generated andtransmitted at the AP 104, for example, and transmitted to a pluralityof the STAs 106. Although the method 500 is described below with respectto elements of the wireless device 202, those having ordinary skill inthe art will appreciate that other components may be used to implementone or more of the steps described herein.

At a block 502, it is determined whether a communication has beenreceived from each of a plurality of apparatuses. For example, the AP104 may determine whether a packet was received from each of the STAs106 associated with the AP 104. The reception may be performed by thereceiver 212, for example. In some aspects, it may be determined whethera communication has been received within a previous period, for examplea time period since a previous ACK was transmitted. The determinationmay be performed by the processor 204, the signal detector 218, and/orthe DSP 220, for example.

At a block 504, a plurality of indicators signifying a result of thedetermination are generated. In some aspects, each indicator signifies aresult of the determination for a respective one of the plurality ofapparatuses. In some aspects, the plurality of indicators is representedby a bitmap, whereby each indicator is implemented with one bit. Inthese aspects, an order of the bits in the bitmap may be determinedbased on the AIDs of the plurality of apparatuses. The generation may beperformed by the processor 204 and/or the DSP 220, for example.

At a block 506, a communication including the plurality of indicators isbroadcast. The indicators may be broadcast within an information elementin a beacon, for example, or as a separate group ACK including thebitmap. The transmission may be performed by the transmitter 210, forexample.

FIG. 6 is a functional block diagram of another exemplary wirelessdevice 600 that may be employed within the wireless communication system100. The device 600 comprises a determining module 602 for determiningwhether a communication has been received from each of a plurality ofapparatuses within a previous period. The determining module 602 may beconfigured to perform one or more of the functions discussed above withrespect to the block 502 illustrated in FIG. 5. The determining module602 may correspond to one or more of the processor 204, the signaldetector 218, and the DSP 220. The device 600 further comprises agenerating module 604 for generating a plurality of indicators. In someaspects, each indicator signifies a result of the determination for arespective one of the plurality of apparatuses. In some aspects, theindicators are included in a bitmap in which each of the bitscorresponds to a respective one of the plurality of apparatuses. Thegenerating module 604 may be configured to perform one or more of thefunctions discussed above with respect to the block 504 illustrated inFIG. 5. The generating module 604 may correspond to one or more of theprocessor 204 and the DSP 220. The device 600 further comprises atransmitting module 606 for broadcasting a communication including theplurality of indicators. The communication may comprise a group ACK, forexample that is integrated into a beacon or that is transmitted separatefrom the beacon. The transmitting module 606 may be configured toperform one or more of the functions discussed above with respect to theblock 506 illustrated in FIG. 5. The transmitting module 606 maycorrespond to the transmitter 210.

FIG. 7A illustrates an aspect of a method 700 for receiving a group ACK.The method 700 may be used to receive the plurality 400 illustrated inFIG. 4, or another suitable plurality of indicators based on theteachings herein. The plurality 400 may be received and processed at oneof the STAs 106, for example from the AP 104. Although the method 700 isdescribed below with respect to elements of the wireless device 202,those having ordinary skill in the art will appreciate that othercomponents may be used to implement one or more of the steps describedherein.

At a block 702, a communication such as a data packet is transmitted toan apparatus, for example to the AP 104. The communication may compriseany one of a multitude of different types of frames or messages. Thetransmission may be performed by the transmitter 210, for example

At a block 704, a communication comprising a plurality of indicators isreceived from the apparatus. In some aspects, each indicator signifieswhether the apparatus has received a communication from a respectivedevice of a plurality of devices. In some aspects, the plurality ofindicators is represented by a bitmap, whereby each indicator isimplemented with one bit. In some aspects, each of the indicators maysignify whether a communication was received within a previous period,for example a time period since a previous ACK. The reception may beperformed by the receiver 212, for example.

At a block 706, it is determined whether the communication transmittedat the block 702 was received by the apparatus. The determination isbased on at least one of the indicators receive at the block 704. Forexample, an STA which transmitted the communication at the block 702 andreceived the plurality of indicators at the block 704 may determine ifthe communication was received by the AP 104 by indexing into theplurality of indicators using the AID of the STA. A value of theindicator at the index determined by the AID may signify if thecommunication transmitted at the block 702 was properly received. Thedetermination may be performed by the processor 204, the signal detector218, and/or the DSP 220, for example.

If the communication transmitted at the block 702 was not properlyreceived, as determined at the block 706, the communication may beretransmitted at a block 708. The transmitter 210 may perform theretransmission, for example.

FIG. 7B illustrates another aspect of a method 750 for receiving a groupACK. The method 750 may be used to receive at least a portion of theplurality 400 illustrated in FIG. 4, or another suitable plurality ofindicators based on the teachings herein. The plurality 400 may be atleast partially received and processed at one of the STAs 106, forexample from the AP 104. Although the method 750 is described below withrespect to elements of the wireless device 202, those having ordinaryskill in the art will appreciate that other components may be used toimplement one or more of the steps described herein.

At a block 752, at least a portion of a group ACK is received. Forexample, enough of the group ACK may be received for the wireless device202 to determine that the information being received is a group ACK. Insome aspects, the processor 204, the signal detector 218, and/or the DSP220 may determine that the information corresponds to a group ACK basedon header information, or based on contents of the plurality 400, forexample. The reception may be performed by the receiver 212, forexample.

At a block 754, it is determined that no communications have been sentto the device that transmitted the group ACK since a previous ACK wasreceived at the wireless device 202. The determination may be performedby the processor 204 and/or the DSP 220, for example.

At a block 756, reception of any remaining portion of the group ACK isinterrupted and the group ACK is ignored. For example, the processor 204may cease analyzing the group ACK or be precluded from evaluating theplurality 400. Similarly, reception of the remainder of the group ACKmay be stopped at the receiver 212. In this way, when the wirelessdevice 202 is not waiting for acknowledgment of any communications, thewireless device 202 may conserve power by reserving resources that wouldotherwise be allocated to receiving and/or processing the group ACK.

FIG. 8 is a functional block diagram of another exemplary wirelessdevice 800 that may be employed within the wireless communication system100. The device 800 comprises a transmitting module 802 for transmittinga first communication to a first apparatus. The transmitting module 802may be configured to perform one or more of the functions discussedabove with respect to the block 702 illustrated in FIG. 7A. Thetransmitting module 802 may correspond to the transmitter 210, forexample. The device 800 further comprises a receiving module 804 forreceiving a second communication including a plurality of indicatorsfrom the first apparatus. The receiving module 804 may be configured toperform one or more of the functions discussed above with respect to theblock 704 illustrated in FIG. 7A, and/or one or more of the functionsdiscussed above with respect to the block 752 illustrated in FIG. 7B.The receiving module 804 may correspond to the receiver 212, forexample. The device 800 further comprises a determining module 806 fordetermining whether the first communication was received by the firstapparatus based on at least one indicator in the plurality ofindicators. The determining module 806 may be configured to perform oneor more of the functions discussed above with respect to the block 706illustrated in FIG. 7A. In some aspects, the determining module 806 isadditionally or in the alternative configured to perform one or more ofthe functions discussed above with respect to the block 754 and/or theblock 756 illustrated in FIG. 7B. The determining module 806 maycorrespond to the processor 204, the signal detector 218, and/or the DSP220, for example.

As used herein, the term “determining” encompasses a wide variety ofactions. For example, “determining” may include calculating, computing,processing, deriving, investigating, looking up (e.g., looking up in atable, a database or another data structure), ascertaining and the like.Also, “determining” may include receiving (e.g., receiving information),accessing (e.g., accessing data in a memory) and the like. Also,“determining” may include resolving, selecting, choosing, establishingand the like. Further, a “channel width” as used herein may encompass ormay also be referred to as a bandwidth in certain aspects.

As used herein, a phrase referring to “at least one of” a list of itemsrefers to any combination of those items, including single members. Asan example, “at least one of: a, b, or c” is intended to cover: a, b, c,a-b, a-c, b-c, and a-b-c.

The various operations of methods described above may be performed byany suitable means capable of performing the operations, such as varioushardware and/or software component(s), circuits, and/or module(s).Generally, any operations illustrated in the Figures may be performed bycorresponding functional means capable of performing the operations.

The various illustrative logical blocks, modules and circuits describedin connection with the present disclosure may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an application specific integrated circuit (ASIC), a fieldprogrammable gate array signal (FPGA) or other programmable logic device(PLD), discrete gate or transistor logic, discrete hardware componentsor any combination thereof designed to perform the functions describedherein. A general purpose processor may be a microprocessor, but in thealternative, the processor may be any commercially available processor,controller, microcontroller or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

In one or more aspects, the functions described may be implemented inhardware, software, firmware, or any combination thereof. If implementedin software, the functions may be stored on or transmitted over as oneor more instructions or code on a computer-readable medium.Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage media may be anyavailable media that can be accessed by a computer. By way of example,and not limitation, such computer-readable media can comprise RAM, ROM,EEPROM, CD-ROM or other optical disk storage, magnetic disk storage orother magnetic storage devices, or any other medium that can be used tocarry or store desired program code in the form of instructions or datastructures and that can be accessed by a computer. Also, any connectionis properly termed a computer-readable medium. For example, if thesoftware is transmitted from a website, server, or other remote sourceusing a coaxial cable, fiber optic cable, twisted pair, digitalsubscriber line (DSL), or wireless technologies such as infrared, radio,and microwave, then the coaxial cable, fiber optic cable, twisted pair,DSL, or wireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Thus, in some aspects computer readable medium may comprisenon-transitory computer readable medium (e.g., tangible media). Inaddition, in some aspects computer readable medium may comprisetransitory computer readable medium (e.g., a signal). Combinations ofthe above should also be included within the scope of computer-readablemedia.

The methods disclosed herein comprise one or more steps or actions forachieving the described method. The method steps and/or actions may beinterchanged with one another without departing from the scope of theclaims. In other words, unless a specific order of steps or actions isspecified, the order and/or use of specific steps and/or actions may bemodified without departing from the scope of the claims.

The functions described may be implemented in hardware, software,firmware or any combination thereof. If implemented in software, thefunctions may be stored as one or more instructions on acomputer-readable medium. A storage media may be any available mediathat can be accessed by a computer. By way of example, and notlimitation, such computer-readable media can comprise RAM, ROM, EEPROM,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to carryor store desired program code in the form of instructions or datastructures and that can be accessed by a computer. Disk and disc, asused herein, include compact disc (CD), laser disc, optical disc,digital versatile disc (DVD), floppy disk, and Blu-Ray® disc where disksusually reproduce data magnetically, while discs reproduce dataoptically with lasers.

Thus, certain aspects may comprise a computer program product forperforming the operations presented herein. For example, such a computerprogram product may comprise a computer readable medium havinginstructions stored (and/or encoded) thereon, the instructions beingexecutable by one or more processors to perform the operations describedherein. For certain aspects, the computer program product may includepackaging material.

Software or instructions may also be transmitted over a transmissionmedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition oftransmission medium.

Further, it should be appreciated that modules and/or other appropriatemeans for performing the methods and techniques described herein can bedownloaded and/or otherwise obtained by a user terminal and/or basestation as applicable. For example, such a device can be coupled to aserver to facilitate the transfer of means for performing the methodsdescribed herein. Alternatively, various methods described herein can beprovided via storage means (e.g., RAM, ROM, a physical storage mediumsuch as a compact disc (CD) or floppy disk, etc.), such that a userterminal and/or base station can obtain the various methods uponcoupling or providing the storage means to the device. Moreover, anyother suitable technique for providing the methods and techniquesdescribed herein to a device can be utilized.

It is to be understood that the claims are not limited to the preciseconfiguration and components illustrated above. Various modifications,changes and variations may be made in the arrangement, operation anddetails of the methods and apparatus described above without departingfrom the scope of the claims.

While the foregoing is directed to aspects of the present disclosure,other and further aspects of the disclosure may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

What is claimed is:
 1. A method of communicating in a wireless network,the method comprising: determining whether a communication has beenreceived from each of a plurality of apparatuses within a previousperiod; generating a plurality of indicators, each indicator signifyinga result of the determination for a respective one of the plurality ofapparatuses and including information identifying a previouscommunication received from the respective one of the plurality ofapparatuses within the previous period, wherein the plurality ofindicators includes the information identifying the previouscommunication received from at least two different apparatuses;wirelessly broadcasting a beacon associated with a periodicity withwhich the plurality of indicators is to be broadcast; and wirelesslybroadcasting a communication comprising the plurality of indicatorsaccording to a stored schedule indicating the periodicity, wherein thegenerating comprises generating a bitmap comprising the plurality ofindicators having information identifying the previous communicationreceived from the respective one of the plurality of apparatuses withinthe previous period, each of the plurality of indicators comprising abit in the bitmap and signifying the result of the determination for therespective one of the plurality of apparatuses, wherein at least twoindicators of the plurality of indicators in the bitmap include theinformation identifying the previous communication received from the atleast two different apparatuses, and wherein the broadcast communicationincludes the bitmap.
 2. The method of claim 1, wherein the previousperiod comprises a time period since a prior communication wastransmitted that indicated to one or more of the plurality ofapparatuses whether information had been received from the one or moreapparatuses.
 3. The method of claim 2, wherein the previous period isthe same for each of the plurality of apparatuses.
 4. The method ofclaim 2, wherein the previous period for a first of the plurality ofapparatuses is different than the previous period for a second of theplurality of apparatuses.
 5. The method of claim 1, wherein thegenerating comprises generating an information element comprising theplurality of indicators, and wherein the broadcast communicationincludes the information element.
 6. The method of claim 1, wherein aposition of each of the plurality of indicators in the bitmap isdetermined pursuant to an association identifier of the respective oneof the plurality of apparatuses.
 7. The method of claim 1, wherein thecommunication comprises the beacon.
 8. The method of claim 1, furthercomprising: communicating the stored schedule to each of the pluralityof apparatuses.
 9. The method of claim 1, further comprising receiving acommunication from one or more of the plurality of apparatuses withinthe previous period.
 10. An apparatus for communicating in a wirelessnetwork, the apparatus comprising: a processor configured to determinewhether a communication has been received from each of a plurality ofapparatuses within a previous period, and further configured to generatea plurality of indicators, each indicator signifying a result of thedetermination for a respective one of the plurality of apparatuses andincluding information identifying a previous communication received fromthe respective one of the plurality of apparatuses within the previousperiod, wherein the plurality of indicators includes the informationidentifying the previous communication received from at least twodifferent apparatuses; and a transmitter configured to wirelesslybroadcast a beacon associated with a periodicity with which theplurality of indicators is to be broadcast and to wirelessly broadcast acommunication comprising the plurality of indicators according to astored schedule indicating the periodicity, wherein the processor isconfigured to generate the plurality of indicators by generating abitmap comprising the plurality of indicators having informationidentifying the previous communication received from the respective oneof the plurality of apparatuses within the previous period, each of theplurality of indicators comprising a bit in the bitmap and signifyingthe result of the determination for the respective one of the pluralityof apparatuses, wherein at least two indicators of the plurality ofindicators in the bitmap include the information identifying theprevious communication received from the at least two differentapparatuses, and wherein the broadcast communication includes thebitmap.
 11. The apparatus of claim 10, wherein the previous periodcomprises a time period since a prior communication was transmitted thatindicated to one or more of the plurality of apparatuses whetherinformation had been received from the one or more apparatuses.
 12. Theapparatus of claim 11, wherein the previous period is the same for eachof the plurality of apparatuses.
 13. The apparatus of claim 11, whereinthe previous period for a first of the plurality of apparatuses isdifferent than the previous period for a second of the plurality ofapparatuses.
 14. The apparatus of claim 10, wherein the processor isconfigured to generate the plurality of indicators by generating aninformation element comprising the plurality of indicators, and whereinthe broadcast communication includes the information element.
 15. Theapparatus of claim 10, wherein a position of each of the plurality ofindicators in the bitmap is determined pursuant to an associationidentifier of the respective one of the plurality of apparatuses. 16.The apparatus of claim 10, wherein the communication comprises thebeacon.
 17. The apparatus of claim 10, wherein the transmitter isfurther configured to transmit the stored schedule to the plurality ofapparatuses.
 18. The apparatus of claim 10, further comprising areceiver configured to receive a communication from one or more of theplurality of apparatuses within the previous period.
 19. An apparatusfor communicating in a wireless network, the apparatus comprising: meansfor determining whether a communication has been received from each of aplurality of apparatuses within a previous period; means for generatinga plurality of indicators, each indicator signifying a result of thedetermination for a respective one of the plurality of apparatuses andincluding information identifying a previous communication received fromthe respective one of the plurality of apparatuses within the previousperiod, wherein the plurality of indicators includes the informationidentifying the previous communication received from at least twodifferent apparatuses; means for wirelessly broadcasting a beaconassociated with a periodicity with which the plurality of indicators isto be broadcast; and means for wirelessly broadcasting a communicationcomprising the plurality of indicators according to a stored scheduleindicating the periodicity, wherein the means for generating isconfigured to generate a bitmap comprising the plurality of indicatorshaving information identifying a previous communication received fromthe respective one of the plurality of apparatuses within the previousperiod, each of the plurality of indicators comprising a bit in thebitmap and signifying the result of the determination for the respectiveone of the plurality of apparatuses, wherein at least two indicators ofthe plurality of indicators in the bitmap include the informationidentifying the previous communication received from the at least twodifferent apparatuses, and wherein the broadcast communication includesthe bitmap.
 20. A non-transitory computer readable medium comprisinginstructions that when executed cause an apparatus to: determine whethera communication has been received from each of a plurality ofapparatuses within a previous period; generate a plurality ofindicators, each indicator signifying a result of the determination fora respective one of the plurality of apparatuses and includinginformation identifying a previous communication received from therespective one of the plurality of apparatuses within the previousperiod, wherein the plurality of indicators includes the informationidentifying the previous communication received from at least twodifferent apparatuses; generate a bitmap comprising the plurality ofindicators having information identifying the previous communicationreceived from the respective one of the plurality of apparatuses withinthe previous period, each of the plurality of indicators comprising abit in the bitmap and signifying the result of the determination for therespective one of the plurality of apparatuses, wherein at least twoindicators of the plurality of indicators in the bitmap include theinformation identifying the previous communication received from the atleast two different apparatuses; wirelessly broadcast a beaconassociated with a periodicity with which the plurality of indicators isto be broadcast; and wirelessly broadcast a communication comprising theplurality of indicators according to a stored schedule indicating theperiodicity, wherein the broadcast communication includes the bitmap.21. A method of communicating in a wireless network, the methodcomprising: wirelessly transmitting a first communication to a firstapparatus; wirelessly receiving a second communication from the firstapparatus, the second communication comprising a plurality of indicatorssignifying whether the first apparatus received a communication fromeach of a plurality of apparatuses; determining whether the firstcommunication was received by the first apparatus based on at least oneindicator of the plurality of indicators; and receiving anacknowledgement from the first apparatus prior to wirelesslytransmitting the first communication, wherein the first communication istransmitted from a second apparatus, and wherein the at least oneindicator signifies whether the first apparatus received a communicationfrom the second apparatus after the acknowledgement was received. 22.The method of claim 21, wherein the acknowledgement comprises a groupacknowledgement.
 23. The method of claim 21, wherein the acknowledgementcomprises an acknowledgment addressed to only the second apparatus. 24.The method of claim 21, wherein the plurality of indicators are includedin an information element.
 25. The method of claim 21, wherein theplurality of indicators are included in a bitmap.
 26. The method ofclaim 25, wherein each of the plurality of indicators comprises a bit inthe bitmap.
 27. The method of claim 25, wherein the first communicationis transmitted from a second apparatus, wherein the method furthercomprises determining a position of the at least one indicator based onan association identifier of the second apparatus.
 28. The method ofclaim 21, wherein the second communication comprises a beacon.
 29. Themethod of claim 21, further comprising receiving a beacon, and whereinthe second communication is received a scheduled time after receivingthe beacon.
 30. A method of communicating in a wireless network, themethod comprising: wirelessly transmitting a first communication to afirst apparatus; wirelessly receiving a second communication from thefirst apparatus, the second communication comprising a plurality ofindicators signifying whether the first apparatus received acommunication from each of a plurality of apparatuses; determiningwhether the first communication was received by the first apparatusbased on at least one indicator of the plurality of indicators; andreceiving at least a portion of a third communication comprising aplurality of indicators signifying whether the first apparatus receiveda communication from each of a plurality of apparatuses since thereception of the second communication, and ignoring the thirdcommunication.
 31. An apparatus for communicating in a wireless network,the apparatus comprising: a transmitter configured to wirelesslytransmit a first communication to a first apparatus; a receiverconfigured to wirelessly receive a second communication from the firstapparatus, the second communication comprising a plurality of indicatorssignifying whether the first apparatus received a communication fromeach of a plurality of apparatuses; and a processor configured todetermine whether the first communication was received by the firstapparatus based on at least one indicator of the plurality ofindicators, wherein the receiver is further configured to receive anacknowledgement from the first apparatus prior to the firstcommunication being transmitted, and wherein the at least one indicatorsignifies whether the first apparatus received a communication from theapparatus for communicating in a wireless network after theacknowledgement was received.
 32. The apparatus of claim 31, wherein theacknowledgement comprises a group acknowledgement.
 33. The apparatus ofclaim 31, wherein the acknowledgement comprises an acknowledgmentaddressed to only the apparatus for communicating in a wireless network.34. The apparatus of claim 31, wherein the plurality of indicators areincluded in an information element.
 35. The apparatus of claim 31,wherein the plurality of indicators are included in a bitmap.
 36. Theapparatus of claim 35, wherein each of the plurality of indicatorscomprises a bit in the bitmap.
 37. The apparatus of claim 35, whereinthe processor is configured to determine a position of the at least oneindicator based on an association identifier of the apparatus forcommunicating in a wireless network.
 38. The apparatus of claim 31,wherein the second communication comprises a beacon.
 39. The apparatusof claim 31, wherein the receiver is further configured to receive abeacon, and wherein the second communication is received a scheduledtime after receiving the beacon.
 40. An apparatus for communicating in awireless network, the apparatus comprising: a transmitter configured towirelessly transmit a first communication to a first apparatus; areceiver configured to wirelessly receive a second communication fromthe first apparatus, the second communication comprising a plurality ofindicators signifying whether the first apparatus received acommunication from each of a plurality of apparatuses; and a processorconfigured to determine whether the first communication was received bythe first apparatus based on at least one indicator of the plurality ofindicators, wherein the receiver is further configured to receive atleast a portion of a third communication comprising a plurality ofindicators signifying whether the first apparatus received acommunication from each of a plurality of apparatuses since thereception of the second communication, and wherein the processor isfurther configured to ignore the third communication.
 41. An apparatusfor communicating in a wireless network, the apparatus comprising: meansfor wirelessly transmitting a first communication to a first apparatus;means for wirelessly receiving a second communication from the firstapparatus, the second communication comprising a plurality of indicatorssignifying whether the first apparatus received a communication fromeach of a plurality of apparatuses; means for determining whether thefirst communication was received by the first apparatus based on atleast one indicator of the plurality of indicators; and means forreceiving an acknowledgement from the first apparatus prior towirelessly transmitting the first communication, wherein the firstcommunication is transmitted from a second apparatus, and wherein the atleast one indicator signifies whether the first apparatus received acommunication from the second apparatus after the acknowledgement wasreceived.
 42. A non-transitory computer readable medium comprisinginstructions that when executed cause an apparatus to: wirelesslytransmit a first communication to a first apparatus; wirelessly receivea second communication from the first apparatus, the secondcommunication comprising a plurality of indicators signifying whetherthe first apparatus received a communication from each of a plurality ofapparatuses; determine whether the first communication was received bythe first apparatus based on at least one indicator of the plurality ofindicators; and receive an acknowledgement from the first apparatusprior to wirelessly transmitting the first communication, wherein thefirst communication is transmitted from a second apparatus, and whereinthe at least one indicator signifies whether the first apparatusreceived a communication from the second apparatus after theacknowledgement was received.